FI57222B - ANORDINATION FOR MAGNETIC FORMATION OF ROBFORM FOR METAL ARCTING - Google Patents

Description

GSS ^ M (11) KUUJ UTUSJULKA, SU C9000 Μλ L J '; UTLÄGGN 1 NCSSKRIFT 5 (i C 2 ^ @ 5 C (45) F: \ t-: r, tM 'Lty 10 7! Ojq ^' ^ (S1) <v.ik? /Tm.ci.^ B 21 D 26/14 // B 21 D 26/00 FINLAND —FINLAND pi) ^ nlhilHiiNi-PitMtneMii 3077/72 (22) H »k * ml« p & lvt — Aiwekninpdt (03-11.72 (23) Alkupaivt — Glteighaudag 03.11-72 (41) ) Tullut lulklMluI - BIMt offwitllg 06.05.73

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Patani och raglftantyralaan 'AnaMctn inligd och utUki ^ n publfcand 31.03.80 (32) (33) (31) Requested «TuoUctus - Begird priority 05.11 · 71

Switzerland-Switzerland (CH) 16110/71 (71) Aluminum Suisse SA, Chippie, Switzerland-Switzerland (CH) (72) Christian Albert Queyroix, Paramans, France-Frankfurt (FR) (7M Berggren Oy Ab (5 * 0 for magnetic working of metal workpieces - Anordning för magnetisk formning av rörformiga, metalliska arbetsstycken

The present invention relates to an apparatus according to the preamble of claim 1 for magnetically shaping tubular metal workpieces.

It is known to form impressions on a metallic tubular body by magnetic shaping. For this purpose, a tubular metal body is fitted between the coil and the matrix, whereby the discharge of a capacitor into the coil provides an induction current to said metal body, the interaction between the coil's magnetic field and induction field in accordance with.

The matrices used hitherto are mainly molds in construction and have two rigid mold halves which are spaced apart to place the workpiece in place and which are then brought closer together so that the matrix closes (cf. DE patent 1,122,188, U.S. patent 3,550,050). »FR patent 1,512,119 · However, the disadvantage of these matrices is that the joint plane of the two parts of the matrix, i.e. the molds, leaves a mark on the magnetically modified object and this trace cannot be completely eliminated even with a very precise printing operation. difficult, if not impossible, simply by separating the two half-cylindrical mold halves from each other when the matrix has depressions terminating in the vicinity of the joint plane, in which case it is necessary to divide the matrix shells into several parts and radially extend them, which greatly complicates the matrix v and leaves traces of joint levels.

The object of the present invention is to obviate the above-mentioned drawbacks and to provide a device with which a tubular metal workpiece can be magnetically shaped without leaving traces on its surface. In order to fulfill this object, the invention is characterized by what is set forth in the characterizing part 1 of the appended claim.

The elastically deformable sleeve is one-piece and leaves no marks. It automatically centers the workpiece during machining and allows for a significantly higher working speed thanks to the cooling option.

However, it is known in the field of magnetic shaping to use elastic materials for the transfer of pressures (DE publication 1 283 187) or elastic presses (DE publication 1 452 661), which are used in repetitive work operations and always return to their original shape. However, no hydraulically known patterned elastic sleeve - as in the present invention - can be deduced from these publications.

The sleeve according to the invention is preferably reinforced with reinforcing elements incorporated therein, for example with metal wires. The reinforcing elements may be divided into the circumference of the sleeve and held together by a screw spring surrounding them. The sleeve may also be surrounded by an au-cut steel tube.

The accompanying drawing shows by way of example some embodiments of the invention.

Figure 1 is an axial sectional view of a device according to the invention.

Figure 2 shows a first embodiment of the device in radial section.

Figure 3 shows the second embodiment in radial section.

Figure 4 shows a third embodiment in radial section.

The matrix shown in Figure 1 consists of a hollow rigid body 1, which is made of metal but may also be of synthetic material, for example nylon, and has two opposite circular openings 2 and 3 to which a resiliently deformable material 57222, e.g. is 75-80 ° Shore A, 4 ends of the tubular housing. The inner surface of the housing has embossments 5, which in this exemplary case are annular recesses. The ends of the housing 4 are fixed to the body 1 by means of two mechanically or magnetically inflated rings 6 and 7 so as to press the edge of the housing 4 between the body 1.

The housing 4 and the cylindrical jacket of the body 1 thus delimit in this way a hermetically sealed annular chamber 8, which may be connected by a line 9 to a liquid source, for example pressure oil.

A magnetic forming coil 10 is arranged concentric with the cylindrical body 1 and the housing 4, into which capacitors (not shown) are discharged. Custom object is a metal tubular blank 11, which is applied parallel to the axis of the matrix between the coil 10 and the housing 4, the direction indicated by the arrow F in this example.

When the can 11 is in place, a pressurized oil is introduced into the chamber 8, whereby the pressure causes the housing 4 to press against the can 11, as indicated in point 4 '. The discharge current then enters the coil 10 and the can 11 deforms by expanding radially according to the embossed pattern 5 of the matrix. After that, it is only necessary to lower the oil pressure in the chamber 8 so that the housing 4 can return to its original position due to its flexibility. The purpose of the expansion of the sleeve 4 is removed from the 'magnetic automatically update the can matrix embossment, in which case it can be pulled out in the axial direction of the arrow F' in the direction. If you want to make deep depressions, it may happen that returning the housing 4 to its rest position is not enough to completely remove the can. In that case, a vacuum must be applied to the chamber 8 to bring the housing 4 into position 4f 'for the time that the can 11 is pulled out.

The advantages of this matrix, which are clear from the drawing, are the following: - it does not have a joint plane which easily leaves a mark on the magnetically modified can; - automatic detachment of the worked object allows easy removal; the object to be modified is automatically centered relative to the axis of the matrix and the coil during compression of the matrix; - the placement of the object to be edited in the matrix takes place completely and automatically; - ease of manufacture;

Claims (13)

4 57222 - easy-to-implement automation by conventional means; - the possibility to cool the matrix with compressed oil, resulting in large production runs without the risk of damaging the matrix or damaging the induction coil. When a magnetic impulse occurs, the housing 4 is subjected to a very strong shock. It may be appropriate to reinforce this housing so that it can more easily withstand this shock. Figures 2, 3 and 4 show three possible solutions as examples. In the embodiment shown in Figure 2, the housing 4 is surrounded by a tubular steel coating 12 which is split along the development line 13 and which forms a suspension. In the embodiment shown in Figure 3, the housing 4 is surrounded by four cylindrical parts 14, 15, 16 and 17 separated by space and held against the housing 4 by a predetermined number of cylindrical coil springs 18. In the embodiment shown in Figure 4, the housing 4 is surrounded by metal wires 19 embedded in the housing mass. and extend parallel to the housing 4 or helically. In a variation of the embodiment shown in Figure 1, the housing 4 could be in its rest position in the position 4 ', whereby the matrix would be open, i.e. in position 4 or 4 ·', creating a vacuum in the chamber 8. On the other hand, since the matrix consists of one piece and the resultant of the expansion forces is basically zero, it does not necessarily have to be very firmly attached to its base, i.e. the machine body, but can be fitted to a movable arm and pushed around the coil. In this case, therefore, the opening 2 can be omitted. Apparatus for magnetically forming tubular metal workpieces, comprising a cylindrical mold (1, 4) with an inlet (2, 3) for a cylindrical expansion coil (10) and a workpiece (11) to be fitted between the coil and the mold, characterized by a rigid hollow body ( 1) with at least one opening (2, 3) and an elastically deformable unitary sleeve (4) with a movable pattern (5) of recesses and / or protrusions on the inner circumference, both ends of which are fixedly connected to the hollow body, wherein either one open end of the sleeve is fixedly fitted to the inlet or both open ends of the sleeve are each fitted to their own inlet of the hollow body so as to form a hermetically sealed annular space (8) between the outer wall of the sleeve and the inner wall of the hollow body. with connections (9) for introducing or removing the pressure medium into the annular space (8) and / or i to create a vacuum in this ring space. Device according to Claim 1, characterized in that reinforcing elements (19), in particular metal wires, are incorporated in the material of the sleeve (4). Device according to Claim 2, characterized in that the metal wires (19) extend parallel to the axis of the sleeve. Device according to Claim 2, characterized in that the metal wires run in a helical shape. Device according to Claim 1, characterized in that a plurality of reinforcing elements (14-17) are distributed on the outer circumference of the sleeve (4) and are held together by at least one helical spring (18) surrounding them. Device according to Claim 5, characterized in that the reinforcing elements (14-17) form longitudinally divided cylinder parts. Device according to Claim 1, characterized in that the sleeve (4) is surrounded by a steel tube (12) with a longitudinal slot (13). Device according to one of Claims 1 to 7, characterized in that the hollow body (1) is made of metal. Device according to one of Claims 1 to 7, characterized in that the hollow body (1) is made of plastic, in particular polyamide. Device according to one of Claims 1 to 9, characterized in that the sleeve (4) is made of natural rubber. Device according to Claim 10, characterized in that the Shore hardness A of the rubber is 75 to 80. 1. An apparatus for forming of the tubular of magnetic, metalliska workpieces, which comprises a cylindrical form (1, 4) with a införings-opening (2, 3) for a cylindrical expansionsspole (10) and for och det between the roll anpassade shape of the workpiece (11) , k e nkn e-tecknad av en stel ihälig kropp (1) med ätminstone en öppning (2, 3) och en elastiskt formningsbar enhetlig sleeve (4) i dess inre, vilken vid sin inre omkrets uppärär av av fördjupningar och / eller upphöjningar bildade formmönstret (3) som skall överföras; och vars